#include<iostream>
#include <vector>
#include <iterator>
#include <algorithm>
using namespace std;

/**
 * @brief 
 * 
 * @return int 
 */

int main()
{
    vector<int> a{1,2,3,4,5,6,7};
    copy(a.begin(), a.end(), ostream_iterator<int>(cout, "\t"));
    cout << "\n";
    random_shuffle(a.begin(), a.end());
    copy(a.begin(), a.end(), ostream_iterator<int>(cout, "\t"));

    cout << "\n";
    // swap(a.begin(), a.begin()+1);
    return 0;
}